Low-temperature-resistant ethylene propylene diene monomer material and preparation method thereof

Abstract

The invention relates to the technical field of rubber material preparation, in particular to a low-temperature-resistant ethylene propylene diene monomer material and a preparation method thereof. The low-temperature-resistant ethylene propylene diene monomer material is prepared from the following raw material components in parts by mass: 50 to 70 parts of ethylene propylene diene monomer, 15 to 25 parts of natural rubber, 15 to 25 parts of butyl rubber, 40 to 50 parts of carbon black, 5 to 15 parts of clay and 20 to 48 parts of plasticizer, 1-3 parts of stearic acid, 3-7 parts of zinc oxide, 1-3 parts of an anti-aging agent, 1-3 parts of a vulcanizing agent, 1-3 parts of an accelerant and 0.5-1.5 parts of a dispersing agent. By selecting the proper rubber matrix, filler, plasticizer and cross-linking system, the flexibility of the ethylene propylene diene monomer in a low-temperature environment can be remarkably improved, meanwhile, the prepared rubber can keep good mechanical performance, and the low-temperature use performance of the automobile pipeline can be effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of rubber materials, and in particular to a low-temperature resistant EPDM rubber material and a preparation method thereof. Background Art

[0002] The engine cooling system of commercial vehicles is a key part of the normal use of the vehicle, and the cooling pipe is a relatively weak part in the cooling system. In a low-temperature environment, if the material used in the pipe has poor low-temperature performance, it will cause the pipe to leak or even fall off, reducing the coolant in the cooling system, and in severe cases even causing the engine to burn out. Therefore, there are higher requirements for the low-temperature performance of the cooling pipe material.

[0003] EPDM (ethylene propylene diene monomer) is commonly used in commercial vehicle cooling pipe materials. It has good weather resistance, ozone resistance and electrical insulation, and is widely used in various fields such as automotive pipes. However, in some applications, especially in low temperature environments, the flexibility and mechanical properties of EPDM may be affected. In order to improve these properties, various plasticizers, fillers and other additives are usually added, but the existing formulas still find it difficult to meet the requirements of low temperature performance and mechanical strength at the same time. Summary of the invention

[0004] Based on this, it is necessary to provide a low-temperature resistant EPDM rubber material and a preparation method thereof. This application can significantly improve the flexibility of EPDM rubber in a low-temperature environment by selecting a suitable rubber matrix, filler, plasticizer and cross-linking system. At the same time, the prepared rubber can maintain good mechanical properties and effectively improve the low-temperature performance of automobile pipelines.

[0005] In the first aspect of the present application, there is provided an EPDM rubber material, which comprises the following raw material components in parts by mass: 50-70 parts of EPDM rubber, 15-25 parts of natural rubber, 15-25 parts of butyl rubber, 40-50 parts of carbon black, 5-15 parts of clay, 20-48 parts of plasticizer; 1-3 parts of stearic acid, 3-7 parts of zinc oxide, 1-3 parts of antioxidant, 1-3 parts of vulcanizer, 1-3 parts of accelerator, and 0.5-1.5 parts of dispersant.

[0006] In some embodiments, the EPDM rubber satisfies at least one of the following conditions (1)-(2):

[0007] (1) The ethylene content in the EPDM rubber is 50%-55%.

[0008] (2) The content of the third monomer in the EPDM rubber is 5%-6%.

[0009] In some embodiments, the Mooney viscosity (ML1+8, 125°C) of the natural rubber is 20-40. In some embodiments, the Mooney viscosity (ML1+8, 125°C) of the butyl rubber is 40-60.

[0010] In some embodiments, the STSA specific surface area of ​​the carbon black is 70 m 2 / g-80m 2 / g, DBP value is 100-110; the filler is nano clay.

[0011] In some embodiments, the nanoclay satisfies at least one of the following conditions (1)-(3):

[0012] (1) The nanoclay is organically modified montmorillonite;

[0013] (2) The average particle size of the nanoclay is 4 μm-8 μm;

[0014] (3) The interplanar spacing of the nanoclay crystals is 18Å-20Å.

[0015] In some embodiments, the plasticizer includes paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid.

[0016] In some embodiments, the mass ratio of the paraffin oil, cyclohexane oil, polyester plasticizer and ionic liquid is 5-12:5-12:5-12:5-12.

[0017] In some embodiments, the antioxidant includes at least one of antioxidant 4020, antioxidant 4010NA, and antioxidant 2246; and the vulcanizing agent is vulcanizing agent TMTD.

[0018] In some embodiments, the accelerator is compounded by trimethylolpropane trimethacrylate and dibenzothiazole disulfide, and the weight ratio of the trimethylolpropane trimethacrylate to the dibenzothiazole disulfide is 0.5-2:1.

[0019] A second aspect of the present invention provides a method for preparing the EPDM rubber material according to the first aspect, the method comprising the following steps:

[0020] S1: Add EPDM rubber, natural rubber, butyl rubber, carbon black, filler, stearic acid, zinc oxide, antioxidant and dispersant into an internal mixer and mix them, then add plasticizer and continue to mix evenly to obtain a mixture.

[0021] S2: The mixed material in step S1 is transferred to an open mixing mill for thin passing and further mixing.

[0022] S3: Cool down to below 100°C, add vulcanizing agent and accelerator, mix well, and obtain a mixed rubber material.

[0023] S4: The mixed rubber is calendered or extruded and vulcanized to obtain the desired product shape.

[0024] In S2, the number of thin passes is 2-3 times; the rubber material is cooled after each thin pass; in S3, the mixing time is 2min-3min; in S4, the vulcanization temperature is 140℃-160℃.

[0025] The present application improves the flexibility and sealing of rubber by blending EPDM, natural rubber and butyl rubber; at the same time, nanoclay and plasticizer are added for blending, and the nanoclay lamellar structure can be dispersed between polymer segments, increasing the spacing between segments. The lamellar structure is easy to slide and has a certain lubricity, making the segments easier to move relative to each other, further improving the flexibility and low-temperature performance of the rubber. Plasticizer molecules or ions can be dissolved or dispersed between polymer segments, and can also improve the flexibility and low-temperature performance of the rubber. The rubber material prepared in the present application not only has excellent low-temperature performance, but also has good mechanical properties, wear resistance, and excellent sealing and aging resistance. The prepared rubber material can effectively improve the sealing reliability of cooling pipelines under low-temperature environments. DETAILED DESCRIPTION

[0026] References to embodiments of the present application will now be provided in detail, one or more embodiments of which are described below. Each embodiment is provided as an explanation rather than a limitation of the present application. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made to the present application without departing from the scope or spirit of the present application. For example, a feature described or described as part of one embodiment may be used in another embodiment to produce a further embodiment.

[0027] Therefore, it is intended that the present application covers such modifications and variations that fall within the scope of the appended claims and their equivalents. Other objects, features and aspects of the present application are disclosed in or are apparent from the following detailed description. It will be appreciated by those of ordinary skill in the art that this discussion is merely a description of exemplary embodiments and is not intended to limit the broader aspects of the present application.

[0028] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0029] In this application, when it comes to numerical ranges, unless otherwise specified, the above numerical ranges are deemed to be continuous and include the minimum and maximum values ​​of the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0030] In this article, when referring to the unit of a data range, if there is a unit only after the right endpoint, it means that the units of the left and right endpoints are the same. For example, 100~150 nm means that the units of the left endpoint "100" and the right endpoint "150" are both nm (nanometers).

[0031] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0032] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.

[0033] Unless otherwise specified, all steps of the present application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, mentioning that the method may also include step (c) means that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0034] If there is no special explanation, the "include" and "comprising" mentioned in this application are open-ended or closed-ended. For example, the "include" and "comprising" may mean that other components not listed may also be included or only the listed components may be included or only the listed components may be included.

[0035] If not specifically stated, in this application, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0036] In view of the problem that the low-temperature performance of automobile pipe materials in traditional technology is poor and it is difficult to balance low-temperature performance and mechanical strength, the present application proposes a low-temperature resistant EPDM rubber material and a preparation method thereof to solve the above-mentioned technical problems existing in rubber materials for cooling pipes of traditional automobiles, especially commercial vehicles.

[0037] In the first aspect of the present application, there is provided an EPDM rubber material, which comprises the following raw material components in parts by mass: 50-70 parts of EPDM rubber, 15-25 parts of natural rubber, 15-25 parts of butyl rubber, 40-50 parts of carbon black, 5-15 parts of clay, 20-48 parts of plasticizer; 1-3 parts of stearic acid, 3-7 parts of zinc oxide, 1-3 parts of antioxidant, 1-3 parts of vulcanizer, 1-3 parts of accelerator, and 0.5-1.5 parts of dispersant.

[0038] In some embodiments of the present application, the EPDM rubber material includes the following raw material components by mass: 60-65 parts of EPDM rubber, 15-20 parts of natural rubber, 15-20 parts of butyl rubber, 40-45 parts of carbon black, 10-15 parts of clay, 40-48 parts of plasticizer; 1-3 parts of stearic acid, 3-7 parts of zinc oxide, 1-3 parts of antioxidant, 1-3 parts of vulcanizer, 1-3 parts of accelerator, and 1-1.5 parts of dispersant.

[0039] The present application improves the flexibility and sealing of rubber by blending EPDM, natural rubber and butyl rubber; at the same time, nanoclay and plasticizer are added for blending, and the nanoclay lamellar structure can be dispersed between polymer segments, increasing the spacing between segments. The lamellar structure is easy to slide and has a certain lubricity, making the segments easier to move relative to each other, further improving the flexibility and low-temperature performance of the rubber. Plasticizer molecules or ions can be dissolved or dispersed between polymer segments, and can also improve the flexibility and low-temperature performance of the rubber. The rubber material prepared in the present application not only has excellent low-temperature performance, but also has good mechanical properties, wear resistance, and excellent sealing and aging resistance. The prepared rubber material can effectively improve the sealing reliability of cooling pipelines under low-temperature environments.

[0040] In some embodiments, the EPDM rubber satisfies at least one of the following conditions (1)-(2):

[0041] (1) The ethylene content in the EPDM rubber is 50%-55%, including but not limited to 50%, 51%, 52%, 53%, 54%, 55%, preferably 50%.

[0042] (2) The content of the third monomer in the EPDM rubber is 5%-6%, including but not limited to 5%, 5.2%, 5.4%, 5.5%, 5.8%, 6%, preferably 5.5%.

[0043] It can be understood that the third monomer refers to the non-conjugated diene substance other than ethylene and propylene in EPDM rubber; the third monomer is selected from ethylidene norbornene (ENB), dicyclopentadiene (DCPD) or 1,4-hexadiene (HD); more preferably, the third monomer is ethylidene norbornene (ENB).

[0044] Preferably, the EPDM rubber is Keltan 5170 from ARLANXEO.

[0045] It is understandable that the present application uses EPDM rubber with a low ethylene content, which can increase the side chains of the molecular chain, increase the distance between chain segments, improve the flexibility of the rubber, and improve the low-temperature performance.

[0046] In some embodiments, the Mooney viscosity (ML1+8, 125° C.) of natural rubber (NR) is 20-40; and the Mooney viscosity (ML1+8, 125° C.) of butyl rubber (IIR) is 40-60.

[0047] Preferably, the natural rubber is STR 20. Preferably, the butyl rubber is ExxonMobil Butyl 268.

[0048] It is understandable that the present application improves the flexibility and sealing of rubber by introducing natural rubber and butyl rubber into the blend with EPDM rubber. Specifically, the low temperature performance of EPDM rubber is improved and the rubber softness is increased by blending the modified natural rubber; the sealing performance of EPDM rubber is improved by blending the modified butyl rubber.

[0049] In some embodiments, the carbon black has a STSA specific surface area of ​​70 m 2 / g-80m 2 / g, DBP value is 100-110.

[0050] Preferably, the carbon black is Corax N330 (Oliron).

[0051] In some embodiments, the filler is nanoclay.

[0052] In some embodiments, the nanoclay satisfies at least one of the following conditions (1)-(3):

[0053] (1) Nanoclay is montmorillonite that has been organically modified;

[0054] (2) The average particle size of nanoclay is 4 μm-8 μm;

[0055] (3) The interplanar spacing of nanoclay crystals is 18Å-20Å.

[0056] Preferably, the nanoclay is Cloisite 30B (Southern Chemical).

[0057] It can be understood that the present application adds nano-clay fillers to disperse the clay nano-sheet structure between the polymer segments, thereby increasing the spacing between the segments. At the same time, the sheet structure is easy to slide and has a certain lubricity, making it easier for the segments to move relative to each other, thereby making the rubber have better flexibility and better low-temperature performance, and can improve the flexibility and mechanical properties of EPDM rubber.

[0058] In some embodiments, plasticizers include paraffinic oils, naphthenic oils, polyester plasticizers, and ionic liquids.

[0059] In some embodiments, the mass ratio of paraffin oil, naphthenic oil, polyester plasticizer and ionic liquid is 5-12:5-12:5-12:5-12.

[0060] In some embodiments, in the EPDM rubber material, the proportions of paraffin oil, cyclohexane oil, polyester plasticizer and ionic liquid are: 5-12 parts of paraffin oil, 5-12 parts of cyclohexane oil, 5-12 parts of polyester plasticizer, and 5-12 parts of ionic liquid.

[0061] In some embodiments, the EPDM rubber material includes the following raw material components in parts by mass: 50-70 parts of EPDM rubber, 15-25 parts of natural rubber, 15-25 parts of butyl rubber, 40-50 parts of carbon black, 5-15 parts of clay, 5-12 parts of paraffin oil, 5-12 parts of cyclohexane oil, 5-12 parts of polyester plasticizer, 5-12 parts of ionic liquid, 1-3 parts of stearic acid, 3-7 parts of zinc oxide, 1-3 parts of antioxidant, 1-3 parts of vulcanizing agent, 1-3 parts of accelerator, and 0.5-1.5 parts of dispersant.

[0062] Preferably, the paraffin oil is Vivatec 500 (Shell), the naphthenic oil is Nyflex 220 (NYTEX, Nynas), the polyester plasticizer is Jayflex DINP (ExxonMobil), and the ionic liquid is 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF6).

[0063] It is understandable that the present application uses four plasticizers in a mixed manner to avoid the situation where a single plasticizer is easily precipitated at low temperatures, thereby increasing the amount of plasticizer that can be added. Plasticizer molecules or ions can be dissolved or dispersed between polymer segments, thereby improving the flexibility of the rubber and the low-temperature performance of EPDM rubber.

[0064] In some embodiments, the antioxidant includes at least one of antioxidant 4020, antioxidant 4010NA, and antioxidant 2246; and the vulcanizing agent is the vulcanizing agent TMTD (tetramethylthiuram disulfide).

[0065] In some embodiments, the accelerator is compounded with trimethylolpropane trimethacrylate and dibenzothiazole disulfide, and the weight ratio of trimethylolpropane trimethacrylate to dibenzothiazole disulfide is 0.5-2:1, including but not limited to 0.5:1, 1:1, and 2:1.

[0066] Preferably, the dispersant is Clariant Licowax E.

[0067] A second aspect of the present invention provides a method for preparing the EPDM rubber material of the first aspect, comprising the following steps:

[0068] S1: Add EPDM rubber, natural rubber, butyl rubber, carbon black, filler, stearic acid, zinc oxide, antioxidant and dispersant into an internal mixer for preliminary mixing. The mixing time is 9-11 minutes, preferably 10 minutes. Add plasticizer and continue mixing for about 5 minutes. Mix evenly to ensure that the plasticizer is evenly dispersed to obtain a mixture.

[0069] S2: The mixed material in step S1 is transferred to an open mixing mill for thin passing and further mixing.

[0070] S3: Cool down to below 100°C, add vulcanizing agent and accelerator, mix well, and obtain a mixed rubber material.

[0071] S4: The mixed rubber is calendered or extruded and vulcanized to obtain the desired product shape.

[0072] In some embodiments, in S2, the number of thin passes is 2-3 times, including but not limited to 2 times and 3 times; the rubber material is cooled after each thin pass.

[0073] In some embodiments, in S3, the mixing time is 2 min-3 min, including but not limited to 2 min, 2.5 min, and 3 min. The mixing needs to be fast to avoid premature cross-linking reaction.

[0074] In S4, calendering can be performed in a calender, and extrusion can be performed using an extruder; the vulcanization temperature is 140°C-160°C, including but not limited to 140°C, 150°C, and 160°C.

[0075] The following are specific embodiments.

[0076] Example 1

[0077] An EPDM rubber material comprises the following raw material components by mass: 60 parts of EPDM rubber, 20 parts of natural rubber, 20 parts of butyl rubber, 45 parts of carbon black N330, 10 parts of nano clay, 10 parts of paraffin oil, 10 parts of cyclohexane oil, 10 parts of polyester plasticizer, 10 parts of ionic liquid, 2 parts of stearic acid, 5 parts of zinc oxide, 2 parts of antioxidant 4020, 2 parts of vulcanizing agent, 2 parts of accelerator and 1 part of dispersant. Among them, the EPDM rubber is Keltan 5170 (ARLANXEO); the natural rubber is STR 20; the butyl rubber is ExxonMobil Butyl 268; the carbon black is Corax N330 (Oliron); the nanoclay is Cloisite 30B (Southern Chemical); the paraffin oil is Vivatec 500 (Shell), the naphthenic oil is Nyflex 220 (NYTEX, Nynas), the polyester plasticizer is Jayflex DINP (ExxonMobil), the ionic liquid is [BMIM][PF6] 1-butyl-3-methylimidazole hexafluorophosphate; the vulcanizing agent is TMTD (tetramethylthiuram disulfide), the accelerator is a mixture of TMPT (trimethylolpropane trimethacrylate) and MBTS (dibenzothiazyl disulfide), with a weight ratio of 1:1; the antioxidant is antioxidant 4020; and the dispersant is Licowax E (Clariant).

[0078] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0079] S1: Mixing in an internal mixer: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant into an internal mixer for preliminary mixing for about 10 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0080] S2: Thin pass on open mill: Transfer the above mixture to an open mill for thin pass, further mix evenly, and make all components fully dispersed. Thin pass twice, and let the rubber cool for a while after each thin pass.

[0081] S3: Add vulcanizing agent: Cool down to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature crosslinking reaction. The mixing time should be controlled within 3 minutes.

[0082] S4: Molding and vulcanization: The mixed rubber is preformed by a calender and vulcanized in a flat vulcanizer at a vulcanization temperature of 150°C and a vulcanization time of 2 hours.

[0083] Example 2

[0084] An EPDM rubber material includes the following raw material components by weight: 60 parts of EPDM rubber, 20 parts of natural rubber, 20 parts of butyl rubber, 40 parts of carbon black N330, 15 parts of nano clay, 10 parts of paraffin oil, 10 parts of naphthenic oil, 10 parts of polyester plasticizer, 10 parts of ionic liquid, 2 parts of stearic acid, 5 parts of zinc oxide, 2 parts of antioxidant 4020, 2 parts of vulcanizing agent, 2 parts of accelerator, and 1 part of dispersant. The sources and models of the raw materials are the same as those in Example 1.

[0085] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0086] (1) Mixing in an internal mixer: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to an internal mixer for preliminary mixing for about 10 minutes. Add paraffin oil, cyclohexane oil, polyester plasticizer, and ionic liquid and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0087] (2) Thin pass on open mill: Transfer the above mixture to an open mill for thin pass to further mix and evenly disperse the components. Thin pass twice, and let the rubber cool for a while after each thin pass.

[0088] (3) Add vulcanizer: Cool down to 95°C, add vulcanizer and accelerator, and mix quickly to avoid premature crosslinking reaction. The mixing time should be controlled within 3 minutes.

[0089] (4) Molding and vulcanization: The mixed rubber is preformed by a calender and then vulcanized in a flat vulcanizer at a temperature of 150°C and a vulcanization time of 2 hours.

[0090] Example 3

[0091] An EPDM rubber material includes the following raw material components by weight: 60 parts of EPDM rubber, 20 parts of natural rubber, 20 parts of butyl rubber, 45 parts of carbon black N330, 10 parts of nano clay, 12 parts of paraffin oil, 12 parts of naphthenic oil, 12 parts of polyester plasticizer, 12 parts of ionic liquid, 2 parts of stearic acid, 5 parts of zinc oxide, 2 parts of antioxidant 4020, 2 parts of vulcanizing agent, 2 parts of accelerator, and 1 part of dispersant. The sources and models of the raw materials are the same as those in Example 1.

[0092] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0093] (1) Mixing in an internal mixer: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to an internal mixer for preliminary mixing for about 10 minutes. Add paraffin oil, cyclohexane oil, polyester plasticizer, and ionic liquid and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0094] (2) Thin pass on open mill: Transfer the above mixture to an open mill for thin pass to further mix and evenly disperse the components. Thin pass twice, and let the rubber cool for a while after each thin pass.

[0095] (3) Add vulcanizer: Cool down to 95°C, add vulcanizer and accelerator, and mix quickly to avoid premature crosslinking reaction. The mixing time should be controlled within 3 minutes.

[0096] (4) Molding and vulcanization: The mixed rubber is preformed by a calender and then vulcanized in a flat vulcanizer at a temperature of 150°C and a vulcanization time of 2 hours.

[0097] Example 4

[0098] An EPDM rubber material includes the following raw material components by weight: 65 parts of EPDM rubber, 20 parts of natural rubber, 15 parts of butyl rubber, 45 parts of carbon black N330, 10 parts of nano clay, 10 parts of paraffin oil, 10 parts of naphthenic oil, 10 parts of polyester plasticizer, 10 parts of ionic liquid, 2 parts of stearic acid, 5 parts of zinc oxide, 2 parts of antioxidant 4020, 2 parts of vulcanizing agent, 2 parts of accelerator, and 1 part of dispersant. The sources and models of the raw materials are the same as those in Example 1.

[0099] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0100] (1) Mixing in an internal mixer: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to an internal mixer for preliminary mixing for about 10 minutes. Add paraffin oil, cyclohexane oil, polyester plasticizer, and ionic liquid and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0101] (2) Thin pass on open mill: Transfer the above mixture to an open mill for thin pass to further mix and evenly disperse the components. Thin pass twice, and let the rubber cool for a while after each thin pass.

[0102] (3) Add vulcanizer: Cool down to 95°C, add vulcanizer and accelerator, and mix quickly to avoid premature crosslinking reaction. The mixing time should be controlled within 3 minutes.

[0103] (4) Molding and vulcanization: The mixed rubber is preformed by a calender and then vulcanized in a flat vulcanizer at a temperature of 150°C and a vulcanization time of 2 hours.

[0104] Example 5

[0105] An EPDM rubber material includes the following raw material components by weight: 65 parts of EPDM rubber, 15 parts of natural rubber, 20 parts of butyl rubber, 45 parts of carbon black N330, 10 parts of nano clay, 10 parts of paraffin oil, 10 parts of naphthenic oil, 10 parts of polyester plasticizer, 10 parts of ionic liquid, 2 parts of stearic acid, 5 parts of zinc oxide, 2 parts of antioxidant 4020, 2 parts of vulcanizing agent, 2 parts of accelerator, and 1 part of dispersant. The sources and models of the raw materials are the same as those in Example 1.

[0106] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0107] (1) Mixing in an internal mixer: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to an internal mixer for preliminary mixing for about 10 minutes. Add paraffin oil, cyclohexane oil, polyester plasticizer, and ionic liquid and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0108] (2) Thin pass on open mill: Transfer the above mixture to an open mill for thin pass to further mix and evenly disperse the components. Thin pass twice, and let the rubber cool for a while after each thin pass.

[0109] (3) Add vulcanizer: Cool down to 95°C, add vulcanizer and accelerator, and mix quickly to avoid premature crosslinking reaction. The mixing time should be controlled within 3 minutes.

[0110] (4) Molding and vulcanization: The mixed rubber is preformed by a calender and then vulcanized in a flat vulcanizer at a temperature of 150°C and a vulcanization time of 2 hours.

[0111] Example 6

[0112] An EPDM rubber material includes the following raw material components by weight: 50 parts of EPDM rubber, 15 parts of natural rubber, 15 parts of butyl rubber, 45 parts of carbon black N330, 5 parts of nano clay, 5 parts of paraffin oil, 5 parts of naphthenic oil, 5 parts of polyester plasticizer, 5 parts of ionic liquid, 1 part of stearic acid, 3 parts of zinc oxide, 1 part of antioxidant 4020, 1 part of vulcanizing agent, 1 part of accelerator, and 0.5 part of dispersant. The sources and models of the raw materials are the same as those in Example 1.

[0113] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0114] S1: Mixing in an internal mixer: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant into an internal mixer for preliminary mixing for about 9 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0115] S2: Mixing on a mixing mill: Transfer the above mixture to a mixing mill for mixing and further mixing to make each component fully dispersed. Mix three times and allow the rubber to cool for a period of time after each mixing.

[0116] S3: Add vulcanizing agent: Cool down to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature crosslinking reaction. The mixing time should be controlled within 3 minutes.

[0117] S4: Molding and vulcanization: The mixed rubber is preformed by a calender and vulcanized in a flat vulcanizer at a vulcanization temperature of 140°C and a vulcanization time of 2 hours.

[0118] Example 7

[0119] An EPDM rubber material includes the following raw material components by weight: 70 parts of EPDM rubber, 20 parts of natural rubber, 20 parts of butyl rubber, 50 parts of carbon black N330, 10 parts of nano clay, 10 parts of paraffin oil, 10 parts of naphthenic oil, 10 parts of polyester plasticizer, 10 parts of ionic liquid, 3 parts of stearic acid, 7 parts of zinc oxide, 3 parts of antioxidant 4020, 3 parts of vulcanizing agent, 3 parts of accelerator, and 1.5 parts of dispersant. The sources and models of the raw materials are the same as those in Example 1.

[0120] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0121] S1: Mixing in internal mixer: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant into internal mixer for preliminary mixing for about 11 minutes. Add paraffin oil, naphthenic oil, polyester plasticizer, and ionic liquid, and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0122] S2: Thin pass on open mill: Transfer the above mixture to an open mill for thin pass, further mix evenly, and make all components fully dispersed. Thin pass twice, and let the rubber cool for a while after each thin pass.

[0123] S3: Add vulcanizing agent: Cool down to 95°C, add vulcanizing agent and accelerator, mix quickly and evenly to avoid premature crosslinking reaction. The mixing time should be controlled within 2 minutes.

[0124] S4: Molding and vulcanization: The mixed rubber is preformed by a calender and vulcanized in a flat vulcanizer at a vulcanization temperature of 160°C and a vulcanization time of 2 hours.

[0125] Comparative Example 1

[0126] An EPDM rubber material includes the following raw material components by weight: 100 parts of EPDM rubber, 45 parts of carbon black N330, 10 parts of nano clay, 10 parts of paraffin oil, 10 parts of naphthenic oil, 10 parts of polyester plasticizer, 10 parts of ionic liquid, 2 parts of stearic acid, 5 parts of zinc oxide, 2 parts of antioxidant 4020, 2 parts of vulcanizing agent, 2 parts of accelerator, and 1 part of dispersant. The sources and models of the raw materials are the same as those in Example 1.

[0127] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0128] (1) Mixing in an internal mixer: Add EPDM rubber, carbon black, nanoclay, stearic acid, zinc oxide, antioxidant 4020, and dispersant into an internal mixer for preliminary mixing for about 10 minutes. Add paraffin oil, cyclohexane oil, polyester plasticizer, and ionic liquid and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0129] (2) Thin pass on open mill: Transfer the above mixture to an open mill for thin pass to further mix and evenly disperse the components. Thin pass twice, and let the rubber cool for a while after each thin pass.

[0130] (3) Add vulcanizer: Cool down to 95°C, add vulcanizer and accelerator, and mix quickly to avoid premature crosslinking reaction. The mixing time should be controlled within 3 minutes.

[0131] (4) Molding and vulcanization: The mixed rubber is preformed by a calender and then vulcanized in a flat vulcanizer at a temperature of 150°C and a vulcanization time of 2 hours.

[0132] Comparative Example 2

[0133] An EPDM rubber material includes the following raw material components by weight: 60 parts of EPDM rubber, 20 parts of natural rubber, 20 parts of butyl rubber, 55 parts of carbon black N330, 10 parts of paraffin oil, 10 parts of naphthenic oil, 10 parts of polyester plasticizer, 10 parts of ionic liquid, 2 parts of stearic acid, 5 parts of zinc oxide, 2 parts of antioxidant 4020, 2 parts of vulcanizing agent, 2 parts of accelerator, and 1 part of dispersant. The sources and models of the raw materials are the same as those in Example 1.

[0134] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0135] (1) Mixing in an internal mixer: Add EPDM rubber, natural rubber, butyl rubber, carbon black, stearic acid, zinc oxide, antioxidant 4020, and dispersant to an internal mixer for preliminary mixing for about 10 minutes. Add paraffin oil, cyclohexane oil, polyester plasticizer, and ionic liquid and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0136] (2) Thin pass on open mill: Transfer the above mixture to an open mill for thin pass to further mix and evenly disperse the components. Thin pass twice, and let the rubber cool for a while after each thin pass.

[0137] (3) Add vulcanizer: Cool down to 95°C, add vulcanizer and accelerator, and mix quickly to avoid premature crosslinking reaction. The mixing time should be controlled within 3 minutes.

[0138] (4) Molding and vulcanization: The mixed rubber is preformed by a calender and then vulcanized in a flat vulcanizer at a temperature of 150°C and a vulcanization time of 2 hours.

[0139] Comparative Example 3

[0140] An EPDM rubber material includes the following raw material components by weight: 60 parts of EPDM rubber, 20 parts of natural rubber, 20 parts of butyl rubber, 45 parts of carbon black N330, 10 parts of nano clay, 40 parts of paraffin oil, 2 parts of stearic acid, 5 parts of zinc oxide, 2 parts of antioxidant 4020, 2 parts of vulcanizing agent, 2 parts of accelerator, and 1 part of dispersant. The sources and models of the raw materials are the same as those in Example 1.

[0141] The preparation method of the above-mentioned EPDM rubber material is as follows:

[0142] (1) Mixing in an internal mixer: Add EPDM rubber, natural rubber, butyl rubber, carbon black, nano clay, stearic acid, zinc oxide, antioxidant 4020, and dispersant to an internal mixer for preliminary mixing for about 10 minutes. Add paraffin oil, cyclohexane oil, polyester plasticizer, and ionic liquid and continue mixing for about 5 minutes to ensure that the plasticizer is evenly dispersed.

[0143] (2) Thin pass on open mill: Transfer the above mixture to an open mill for thin pass to further mix and evenly disperse the components. Thin pass twice, and let the rubber cool for a while after each thin pass.

[0144] (3) Add vulcanizer: Cool down to 95°C, add vulcanizer and accelerator, and mix quickly to avoid premature crosslinking reaction. The mixing time should be controlled within 3 minutes.

[0145] (4) Molding and vulcanization: The mixed rubber is preformed by a calender and then vulcanized in a flat vulcanizer at a temperature of 150°C and a vulcanization time of 2 hours.

[0146] Comparative Example 4

[0147] An EPDM rubber material, whose raw materials and parts are basically the same as those in Example 1, except that butyl rubber is not added and the natural rubber is 40 parts. The preparation method of the EPDM rubber material is the same as that in Example 1.

[0148] Comparative Example 5

[0149] An EPDM rubber material, the raw materials and the proportions thereof are substantially the same as those in Example 1, except that no natural rubber is added and the butyl rubber is 40 parts. The preparation method of the EPDM rubber material is the same as that in Example 1.

[0150] Comparative Example 6

[0151] An EPDM rubber material, the raw materials and the parts thereof are substantially the same as those in Example 1, except that the nano clay is replaced by ordinary clay. The preparation method of the EPDM rubber material is the same as that in Example 1.

[0152] Comparative Example 7

[0153] An EPDM rubber material, the raw materials and the proportions thereof are substantially the same as those in Example 1, except that only 20 parts of polyester plasticizer and 20 parts of paraffin oil are added. The preparation method of the EPDM rubber material is the same as that in Example 1.

[0154] Test example:

[0155] The EPDM rubber materials prepared in Examples 1 to 5 and Comparative Examples 1 to 7 were subjected to performance tests, and the test results are shown in the following table.

[0156] Table 1 Performance tests of embodiments and comparative examples

[0157]

[0158] As can be seen from the above table, by comparing Example 1 with Comparative Example 1, it can be seen that when only EPDM rubber is used, the Shore A hardness of the prepared EPDM rubber material increases significantly, and the low temperature performance is poor. Comparing Examples 1 and 4 with Comparative Example 4, it can be seen that when the butyl rubber ratio is reduced, its mechanical properties decrease. Comparing Examples 1 and 5 with Comparative Example 5, it can be seen that when the natural rubber ratio is reduced, its low temperature performance decreases. Comparing Example 1 with Comparative Examples 2 and 6, it can be seen that when nanoclay is not added, its low temperature performance deteriorates and the Shore A hardness increases. Comparing Example 1 with Comparative Examples 3 and 7, it can be seen that when only petroleum wax is used or two plasticizers are used, the tensile strength, elongation at break and tear strength are all reduced, and the low temperature performance is poor.

[0159] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0160] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A low temperature resistant EPDM rubber material, characterized in that: By mass, it includes the following raw material components: 50-70 parts of EPDM rubber, 15-25 parts of natural rubber, 15-25 parts of butyl rubber, 40-50 parts of carbon black, 5-15 parts of clay, 20-48 parts of plasticizer; 1-3 parts of stearic acid, 3-7 parts of zinc oxide, 1-3 parts of antioxidant, 1-3 parts of vulcanizing agent, 1-3 parts of accelerator, and 0.5-1.5 parts of dispersant.

2. The low temperature resistant EPDM rubber material according to claim 1, characterized in that: The EPDM rubber satisfies at least one of the following conditions (1)-(2): (1) The ethylene content in the EPDM rubber is 50%-55%; (2) The content of the third monomer in the EPDM rubber is 5%-6%.

3. The low temperature resistant EPDM rubber material according to claim 1, characterized in that: The Mooney viscosity (ML1+8, 125°C) of the natural rubber is 20-40.

4. The EPDM rubber material according to claim 1, characterized in that: The Mooney viscosity (ML1+8, 125°C) of the butyl rubber is 40-60.

5. The low temperature resistant EPDM rubber material according to claim 1, characterized in that: The STSA specific surface area of ​​the carbon black is 70 m 2 / g-80m 2 / g, and a DBP value of 100-110; the clay is nano clay.

6. The low temperature resistant EPDM rubber material according to claim 5, characterized in that: The nanoclay satisfies at least one of the following conditions (1)-(3): (1) The nanoclay is organically modified montmorillonite; (2) The average particle size of the nanoclay is 4 μm-8 μm; (3) The interplanar spacing of the nanoclay crystals is 18Å-20Å.

7. The low temperature resistant EPDM rubber material according to claim 1, characterized in that: The plasticizers include paraffin oil, naphthenic oil, polyester plasticizers and ionic liquids.

8. The low temperature resistant EPDM rubber material according to claim 7, characterized in that: The mass ratio of the paraffin oil, naphthenic oil, polyester plasticizer and ionic liquid is 5-12:5-12:5-12:5-12.

9. The low temperature resistant EPDM rubber material according to claim 1, characterized in that: The antioxidant includes at least one of antioxidant 4020, antioxidant 4010NA, and antioxidant 2246; The vulcanizing agent is vulcanizing agent TMTD; The accelerator is compounded by trimethylolpropane trimethacrylate and dibenzothiazole disulfide, and the weight ratio of the trimethylolpropane trimethacrylate to the dibenzothiazole disulfide is 0.5-2:

1.

10. A method for preparing the low temperature resistant EPDM rubber material according to any one of claims 1 to 9, characterized in that: The preparation method comprises the following steps: S1: Add EPDM rubber, natural rubber, butyl rubber, carbon black, filler, stearic acid, zinc oxide, antioxidant and dispersant into an internal mixer, mix, add plasticizer and continue to mix evenly to obtain a mixture; S2: The mixed material in step S1 is transferred to an open mixing mill for thin passing and further mixing; S3: Cool down to below 100°C, add vulcanizing agent and accelerator, mix evenly, and obtain mixed rubber; S4: The mixed rubber material is calendered or extruded and vulcanized to obtain the desired product shape; In S2, the number of thin passes is 2-3 times; the rubber material is cooled after each thin pass; in S3, the mixing time is 2min-3min; in S4, the vulcanization temperature is 140℃-160℃.

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